USA TODAY - If you are recycling at home, you are probably doing it wrong.

That is why a worker lunged to grab a garden hose off the conveyor belt at a Waste Management recycling facility here Wednesday before it got caught in a giant sorting machine. Such tangles frequently require the plant to stop the waste processing line and clean out the jaws by hand.

"Our contamination changes by the season," said Mike Taylor, the company's director of recycling operations here. Since it's spring, the facility is getting a lot of garden hoses. Around the holidays, they get broken strands of Christmas lights, another choking hazard for the sorting line. And all day every day there are plastic shopping bags (recyclable at a grocery store but not from a household), chunks of styrofoam, diapers, syringes, food-contaminated containers ... a nearly endless litany of things that residents throw into their curbside recycling carts figuring they are or ought to be recyclable. One worker grabs the remnants of a screen door off the sorting line while another snags a wire rack from a DIY shelving unit.

Many cities around the country will celebrate the 47th Earth Day on Saturday by highlighting their recycling programs, but the industry is grappling with a dual threat: The value of recovered waste products has plummeted over the past five years, and the amount of effort required to extract them has risen.

A study by Rob Taylor with the State Recycling Program in the North Carolina Department of Environmental Quality estimated that the average market value of a ton of mixed recyclable material arriving at a recovery facility in the state dropped from just over $180 in early 2011 to less than $80 at the end of 2015. That value has since rebounded a bit, Taylor found, to a little over $100, but it still leaves the industry struggling to extract profit from the millions of tons of recyclable material Americans throw away every year.

There are a host of reasons for the decline in the recycling market, ranging from global trade policy to the decline in newspaper readership, said David Biderman, executive director and CEO of the Solid Waste Association of North America. Much of reclaimed American waste is shipped overseas, but China erected new limits on imported waste in 2013. In other nations, "there has been a decrease in demand for that material as growth rate in foreign countries has leveled off," Biderman said. Low oil prices have made it cheaper to produce new plastic bottles, so manufacturers don't have as much need for reclaimed plastic. In addition, packaging producers have figured out how to make bottles and cans thinner, so they don't need as much raw material.

And as the circulation for print newspapers has plummeted, the recycling industry has lost both a massive customer for reclaimed paper fiber and a huge source of incoming recyclable material.

Across the recycling industry, "what was once a valuable commodity five years ago is less valuable now," Biderman said.

The change is perhaps most dramatic for glass. In most American cities, the glass bottle you toss in the recycling cart is essentially worthless, and if it breaks, the shards may make the paper in a mixed cart worthless as well.

"We work hard to keep glass in the system because it is an iconic recycled item," said Keefe Harrison, CEO of the Recycling Partnership, a non-profit committed to improving recycling programs nationwide. But "it has very minimal market value because it has to compete with sand," which is the raw material glass is made from. Some municipalities have simply stopped collecting glass in their curbside recycling programs. Santa Fe overhauled its recycling program this month and said it would no longer collect glass from households. Residents are being asked to take their glass to four drop-off centers around the city.

The Elkridge facility sorts a lot of glass, Mike Taylor said, but it "doesn't add value" to the waste stream. "You can't move it long distances without paying hefty freight rates," Taylor said, so "it’s a negative-value material for us at the processing facility by the time you separate it and then try to truck it three or four or five hundred miles to get it to a market.”

Much reclaimed glass ends ground into a kind of gravel that can be used in road construction or other industrial projects.

When cities launched recycling programs in the 1980s and 1990s, the theory was that the revenue from the recovered materials would offset the costs of collecting and separating the waste, but it hasn't worked out that way. Kevin Miller, recycling manager for the city of Napa, Calif., said "we get back about 20%" of the costs of collecting, sorting and shipping materials.

Miller and environmental advocates point out that recycling has other economic benefits, such as reducing the use and cost of landfills and reducing the need for harvesting virgin materials.

But the burden of paying for it falls on cities — or residents who pay for the trash service — because the U.S. has not followed the path of many European countries of requiring manufacturers to take responsibility for the disposal or recovery of their products and packaging.

For example, syringes are a major hazard for workers sorting recyclables on the conveyor belts at facilities around the country, said Heidi Sanborn, executive director of the National Stewardship Action Council. But she said in Ontario, Canada, prescriptions for injections come with a return package. "When you get a needle prescription, they hand you a safe-return container," she said. When the syringes are empty, "you bring back your full container of needles (to the pharmacy), they put it in the back in a bin" and a specialty waste contractor picks them up for proper disposal.

Short of take-back programs like that, American cities are taking a variety of steps to address the costs of maintaining their recycling programs. Working with Waste Management, the city of Berwyn, Ill., launched an education program at the beginning of April called "Recycle Often, Recycle Right," which begins with fliers and outreach efforts to educate residents on what should and should not go in their recycling carts. By the end of the month, collectors will refuse to pick up carts that are filled with trash or other contaminants.

"It's all about education," said Assistant City Administrator Ruth Volbre. “People are willing to go ahead with it, they just need the information.”

Des Moines has begun "curbside audits," and recycling bins filled with non-recyclable items will not be picked up. “We’ve had two years in a row of record amounts of recyclables," Public Works Director Jonathan Gano told the city council, according to The Des Monies Register. "But we have record amounts of trash going into the recycling bins.”

This is problem nationwide, Biderman said. "Ten or 15 years ago, to increase recycling rates, we wanted to make it it as easy as possible for Americans to recycle so we told them to put it one big bin," he said. So people are putting everything they think could — or should — be recycled into the bins. "We have a lot of aspirational recyclers," Biderman said. "Contamination rates at recycling facilities have increased significantly over the past five years."

Harrison said her group worked with Lowell, Mass., to send people into the streets to check recycling bins and leave "Oops" tags for residents to explain what materials they should not have dropped there.

But in some places, education is not enough, and local officials are raising fees to offset the reduced value of recovered commodities. Ocala, Fla., approved a rate increase for its recycling program last month and Boulder, Colo., has begun taking steps that could result in a fee increase there as well. Sioux Falls, S.D. raised hauling fees largely to cover the cost of handling glass, and Pendelton, Ore., raised its garbage fees in part because recycling revenues have dropped.

But it is not all bad news in the industry, Napa's Miller said. The growth of online shopping has generated an explosion of cardboard packaging coming into the recycling stream. "there is more corrugated cardboard in the system than ever before," he said, which is a valuable and readily recyclable product — as long as it is not contaminated in a recycling bin by a dirty diaper or broken bottle.